Suffragan of Venice. Concordia is an ancient Venetian city, called by the Romans Colonia Concordia, and is situated between the Rivers Tagliamento and Livenza, not far from the Adriatic. Today there remain of the city only ruins and the ancient cathedral. During the fifth century the city was destroyed by Attila and again in 606 by the Lombards, after which it was never rebuilt. The eighty-nine martyrs of Concordia, who were put to death under Diocletian, are held in great veneration. Its first known bishop is Clarissimus, who, at a provincial synod of Aquileia in 579, helped to prolong the Schism of the Three Chapters; this council was attended by Augustinus, later Bishop of Concordia, who in 590 signed the petition presented by the schismatics to Emperor Mauricius. Bishop Johannes transferred the episcopal residence to Caorle (606), retaining, however, the title of Concordia. The medieval bishops seem to have resided near the ancient cathedral, and to have wielded temporal power, which, however, they were unable to retain. In 1587, during the episcopate of Matteo Sanudo, the episcopal residence was definitely transferred to Portogruaro. The diocese has a population of 258,315, with 129 parishes, 231 churches and chapels, 264 secular and 2 regular priests, 9 religious houses of women, and a Collegio di Pio X for African missions.